1. Field of the Invention
This invention relates to a structure of a front portion of a side frame disposed in the vicinity of a front wheel of a vehicle, and more particularly to a front portion structure of a vehicle frame or a front portion structure which limits the intrusion of the front wheel into a vehicle body at the time of a collision of the vehicle, thereby securing a passenger space.
2. Related Art
In order to solve a problem that a tire intrudes into a body at the time of a collision of a vehicle to thereby reduce a passenger space, there have heretofore been proposed various solving means. Examples of such solving means in a monocoque-body vehicle are disclosed in Japanese Patent Unexamined Publication Nos. 5-116647 and 5-85414.
xe2x80x9cFront Portion Structure of Car Bodyxe2x80x9d, disclosed in Japanese Patent Unexamined Publication No. 5-116647, is directed to a front portion structure of a frame which comprises a front side member, a floor frame which is integrally connected to the front side member, and is connected to rockers and a floor frame in a bifurcated manner, and a sub-frame connected to the front side member and the floor frame, and this front portion structure is provided in that a rear one of two connection portions of a suspension arm, which are connected respectively to the front side member and the floor frame, is disposed between that portion of the sub-frame, connected to the front side member, and that portion of the sub-frame connected to the floor frame. With this connection construction of the suspension arm, that portion of the suspension arm, including the rear connection portion, can be much deformed without being projected at the time of a collision of the vehicle, so that a front wheel is displaced laterally inwardly, and therefore the area of contact between a tire and the members on the vehicle body is large, and the amount of absorbing of an impact energy is large, thereby limiting the intrusion of the front wheel into the vehicle body.
In xe2x80x9cFront Body Portion Structure of Automobilexe2x80x9d disclosed in Japanese Patent Unexamined Publication No. 5-85414, there is provided front wheel-turning means for angularly moving a front wheel right or left at the time of a collision of a vehicle so that a crush stroke between the front wheel and the vehicle body can be increased, thereby limiting the intrusion of the front wheel into the vehicle body. There is also disclosed means in which a slanting surface is formed at that portion of a side sill, against which the front wheel can strike, so as to positively angularly move the front wheel outwardly.
Although the above conventional techniques are effective in limiting the intrusion of the tire into the vehicle body, these are applied to a moncoque-body vehicle as described above, and can not be suitably applied to a recreation vehicle (RV) with a frame. Namely, in the case of the recreation vehicle, it is difficult to provide a large energy-absorbing zone, as obtained in a monocoque-body vehicle, at the front portion. And besides, the structure of that portion of the recreation vehicle, disposed around a front suspension, is rigid, and a condition of deformation thereof is different from that of the monocoque-body vehicle, and it is difficult to apply the above conventional techniques to the recreation vehicle.
In a recreation vehicle, there may be proposed means in which a stopper and so on are provided in a path of movement of a front wheel at the time of a collision so as to mechanically limit the movement of the front wheel. However, a side sill, a torque box, a rocker panel and so on are provided rearwardly of the front wheel, and in some cases, it is not possible to provide the stopper forwardly of these parts so as to limit the movement of the front wheel, and besides if the rigidity of the stopper and the rigidity of that portion around the stopper are inadequate, there is easily encountered a problem that that portion around the stopper is deformed, so that the engagement between the front wheel and the stopper is released, thus failing to limit the movement of the front wheel.
The present invention has been made under the above circumstances, and an object of the invention is to provide a front portion structure of a vehicle frame or front portion structure which can be applied to a recreation vehicle with a frame, and limits the amount of rearward movement of a front wheel at the time of a collision of a vehicle so as to reduce the amount of intrusion of the front wheel into a vehicle body, thereby securing a passenger space.
The above object has been achieved by a front portion structure of a vehicle frame of the invention which is provided at that portion of a side frame disposed in the vicinity of a front wheel, and limits the movement of the front wheel at the time of a collision of a vehicle, provided in that the front portion structure comprises a stopper mounted on and projecting from an outer surface of the side frame, and a reinforcement fixedly secured to an inner surface of that portion of the side frame on which the stopper is mounted; the stopper has such a configuration, and is disposed at such a position that the stopper can abut against a rear side of an outer periphery of the front wheel at the time of a collision of the vehicle; and the reinforcement has a sufficient rigidity to prevent that portion of the side frame, to which the reinforcement is secured, from being deformed by an impact force.
The above object has been achieved by a front portion structure provided in that the front portion structure is fixedly mounted on and projects from an outer surface of that portion of a side frame disposed in the vicinity of a rear side of an outer periphery of a front wheel supported on the side frame through a suspension arm and so on; and the stopper has such a configuration that the stopper can abut against the rear side of the outer periphery of the front wheel at the time of a collision of a vehicle; and the stopper has a sufficient rigidity to prevent the front wheel from coming into contact with the side frame. More specifically, a cross member and/or a front mount bracket are fixedly mounted on that portion of the side frame disposed in the vicinity of the stopper.
In the conventional techniques, at the time of a collision of a vehicle, the front wheel strikes directly against the side frame to greatly deform the side frame. As a result, the front wheel moves toward the vehicle body, thereby reducing the passenger space. In the front portion structure of the vehicle frame according to the present invention, however, there are provided the stopper and the reinforcement, and with this construction, at the time of a collision of the vehicle, the front wheel strikes against the stopper, and also the stopper is reinforced by the reinforcement, and therefore the movement of the front wheel is positively limited by the stopper, and the side frame and so on are deformed only at those portions thereof disposed forwardly of the stopper, and the movement of the front wheel toward the vehicle body is greatly reduced.
In the conventional techniques, at the time of a collision of a vehicle, the front wheel strikes directly against the side frame to greatly deform the sideframe. As a result, the front wheel moves toward the vehicle body, thereby reducing the passenger space.
However, when the stopper of the present invention is provided at the predetermined portion of the side frame, the rear side of the outer periphery of the front wheel strikes against the stopper at the time of a collision of the vehicle, and besides since the stopper has a high rigidity, the contact of the front wheel with the side frame is prevented. As a result, the amount of intrusion of the front wheel into the vehicle body is reduced. Furthermore, the cross member and the front mount bracket are mounted on that portion of the side frame disposed in the vicinity of the stopper, and with this construction, the rigidity of that portion around the stopper is further enhanced, thereby limiting the movement of the front wheel.